strange brown spotting on leaves...??

hey guys, i just noticed today when i got home from work that a few sets of leaves on 2 different plants just startred to show these strange brown spots, not like anything i've seen thus far. take a look at the pix and provide ur opinion please! theyre in bubbleponics, clones, 3 weeks old. it is entirely possible i am under-nuting them so if that looks like the case please say so and ill add a lil more. also i chked the temp of the reservoir by hand earlier, it seemed a bit warmer than i expected, like warmer than water in a fish tank would ever get.. probly 82 degrees. should that stay cooler? thx again 4 feedback.

Did anyone ever answer you? Did you figure out the problem?

I'm having a very similar problem, so if you know what's up, please share the info! If not, anyone else know??

Thanks!

killswitch, u r the 1st one to reply to this thread. and sadly, my babies passed away shortly after those pics were taken. (i hope your girls' fate fares differently). but, perhaps we can identify a common denominator between our girls/setups and subdequently identify the cause of the stragne spotting. let me tell u about my setup and tell me in what ways urs is similar:

-bubbleponics
-400w MH on 24/7
-white widow
-clones
-temperature varied way too much IMHO, (it would range btwn 66 and 86 degrees)
-the avg temp was about 83-85
-humidity around 50-58%
-i did NOT give them any nutes at all for about the first 10 days (i think this was a HUGE mistake, and yes i am a dumbass)... so the only nutes they had for the beginnign there was the nutes supplied through the rooting solution i used when the clones were cut
-i discovered that i was not using enough water to allow the packaged dry nutes to dissolve completely. i only realized this when one of my friends was over while i was mixing the nutes and he commented that maybe the reason my solution never seemed to emulsify completely is b/c i wasnt using enough water.. so that also means that nutes were being added to the rez in an improper way. subsequently, when i was cleaning the system, i discovered the water tubing was full of this nasty nasty splooge looking shit that was uber gross to deal with. that couldnt have helped things.

now, shortly after i took the original pix, i opted to turn the lights off on my girls and allow them to die completely (they were struggling so badly that even if they had survived harvest would have been dismal). from my first grow experience, i learned the following:
-make DAMN sure that u have ventilation figured out if ur using a HID light. they get WAY hotter than i expected, and that is no bueno for la niñas. dont allow temp to vary more than 10 degrees, the less the better.
-dont allow them to get hotter than about 82-83 max (this will vary depending on the strain, but i think this is a good rule of thumb)
-make sure ur not a dumbass like i was and feed them too late. make sure they have food! (duh)

so, any common denominators that u can see?

one of my babies is doing this too. Aeroponics correct nutes 72-78 degrees always fan and well ventilation. It was growing amazing fast seed to 8 inches in about a month and in one day this happens. I turned off all the lighting and am praying it will recover. I think it is a heat issue maybe.

i had a very similar problem, tried everything, turns out my ph was off and the ph tester i was using was crap! i am growing in a drip rockwool setup though

wrong ph will cause all types of other problems, locking out nutrients, imbalancing everything, and the problems will be diplayed as a bit of everything so hard to diagnose........ try mesuring your ph with a different method or someone elses meter or something!

about 2 weeks after correcting the ph, plants seem to be doing allot better, however there are still signs on alot of the fan leaves

I am not sure what my plant is doing it won't die(same problem as mentioned above). I took it out of the aeroponics setup I have and tried putting it into a cup full of lillygro 2/1 mix. I figured it would have died overnight but It actually grew about half an inch and a new set of leaves came up but they are yellow as a pear. I am going to leave it in there for another night to see what happens. Got my hands on some nice clones so I am not worried to much.

it died overnight and the smell of her was overwhelming.

Hello there,

I have almost the same setup, except I'm using HPS (I might be switching to MH for obvious reasons), and my average temperature was much less, and I started from seed. I keep the temp at 70-75. Sometimes, though, it has krept up to 85 which is why I think the brown spotting appeared; It's probably heat stress. My babies are doing much better now that they are out of the heat ( moving them a bit farther from the light helped). Also, yes, the pH can definately cause issues like this. My pH was a bit higher than it should have been which locks out certain nutes ( I think there's a chart on this site somewhere that shows what nutes get locked out at what pH). So, it could have been a combination of heat plus nutes for the both of us. I'll let you know how it works out...

i agree... in fact i didnt mention this earlier but when i first transplanted them, my PH was running on the high side as well.. around 7.25.. but when i put nutes in at about day 10 it helped balance the PH. well, my 2nd go round, i statred with nutes in the water from the git-go, not so much for food but to lower the PH. now my PH stays around 6, which is much closer to where it should be. also, i inverted my lighting schedule, so my plants have 6 hours of darkness during noon-6pm - this is naturally the hottest part of the day anyway, so i figured leaving the light on during the night, which is naturally colder, would help keep the temperature frmo dropping into the 60s which it was doing before, and being off during the day would prevent the temp from climbing above 83ish degrees, since the light would be off. its working fairly well, as much average temps now are 73 degrees at the low, and 82 at the high.

ah, that's very clever. i did that for a while. however, my grow is also in my bedroom. the light was leaking a bit because of ventilation holes and it was messing with my sleep patterns. now i have it set to go off for 3 hours starting at 11 PM and on 21 hours at 2 am (by that time i'm asleep anyway). previously, i had the same setup as you. doing the lights at the time that you are also avoids any type of power short that would happen durring the highest power usage part of the day.

i have a question: is it bad to expose lights to the roots? also, you are suppose to keep light out of the resevoir, correct? (remember i have a small 3 gallon resevoir with a bubble ponics system).

thanks for all your help.

I found the solution to this problem in a high times from 2005. It is a phosphorus deficiency. I added more to my aeroponics setup and it fixed it within a day.